Swivel



C. MILLER Sept. 8, 1953 SWIVEL Filed Aug. 10, 1948 CFC/L M14452 INVENTOR.

' nrroe/ve'v Patented Sept. 8, 1953 UNITED STATES PATENT OFFICE SWIVEL Cecil Miller, Pomona, Calif.

Application August -10, 1948,Serial N 0. 43,372

I "2 Claims.

invention relates generally "to swivels and more'p'artieuiarly' to'a free rotating ball or roller bearingswivd whichis of especial use when embodied ihe'eranehook. "Iti's common practice to swivel eohheetthe 'loadinghook with the line offa. crane or other hoisting device, to prevent t'd'fsifinal strain and "twisting of the line, and my device overoihe's'mah y disadvantages heretoiore encountered in'sii'h "use, although it is not "so limited and "may be employed elsewhere as desired. I

Bykeeping the weight nn'theuhloaded line at 'a' minimum the dangerous "Swinging tendency "of thisfreerwei 'ht is'iedliced, and the device is more efiicient and :ea'sier'to handle. "In addition, it is desirable "that the length or any necessary rigid seetioris hiserte between the hook and the line slioi'ild be kept short,- and any joints which would tend tounscrew'orotherwise give way should be eliminated. The use o'i 'swivel desi'gn and t:OIl'StIllitti0'1);'p'elifiits the HO'Ok OIEYB' to be forged in 'onepie'eewiththeshait member forming an ih'te'graipart 6f the swivel. In effeot, the swivel may be eoii'taihedih the shank of the hook, and the length andw'eight "of such a seeti'on is materially reduced.

It is "another ebjeet offmyi'nve'ntion to supportithe hookfieeiy rotatame within the housihg ih'such amahner that the axial'distance between the 'supportpoint' of the'hook and the lower end of the bearing surface is short, reducing ii'ueh or 'thebe'ndi'n'g stresswhieh-ereates a radial Ioed'o'n 'the'beai'ifig's and tends "to bind the shaft within the swivel, I I

An additionalhbj'ect'of'myinvention is to provide a plurality of ball or other type of rolling eiement'bea'rings which are designed for both a radial andthrust load,'so as to distribute the thrust load axially along the housing and form a large bearing'surfa'c'e for the'distribution of i'adial stresses. [By this design the hook shaft is kept free fromfth'e housing at all 'points and cannot rub or bind against it.

*It'is also'an objec't of myi'nven'tionto provide a swivel of overall streamline 'shape having no abruptploj'eetiOnS-Whih might catch during liftin'g o'rlowering operations on hatch e'dges, beams, or the i'ike, ahdto kee'pthe diameter of the swivel small in order to avoid interfering with the pro er -use of the hook.

still another'cbj'ect of my invention isto provide -'a self lubricating swivel whieh is sealed to retain the lubricant and "to prevent "Contaminatio'n'by dirt'o'r moisture.

A fur h r merit of iriy invention is to provide from an'inspec'tion of the accompanying drawings in which: I I I Fig. 1 is a side'elevationpartiallyin-seetion'of a preferred form'ofmy'inventioh'havihg"a hook type I IOWET coupling "member;

Fig. 2 is a fragmentaryhentral"Vertical section showing the 'detailsof the bearing construction; and

Fig. 3 is aside'elevation ofa'pref'erredform of my inventionhat'ing an eye 'o'rring ty'pe o'f lower'coupling menib'en-With the housingrotat'ed relative'to the endm'em berto show" the "flattened sides of the top coupling member. I

Referring now to the drawing 'andparticula'rly to'Fig. 1 thereof,'the numeral lfl' indieates-asuitable 'shell'or housing ofcylindricalshape hai ing an axial bore H extendingentirely"therethrough, the lower'portion'of the bordbeing reduced to form an internal annular shoulder [2. the-upper-portion of the'bore II female threads Ia-are rovided to receive amele-externauy threaded lower extension or hub M of a top end coupling member I 5. The upper surface-of thisnoupl'ing member 15 forms a vertically flattened block which is cut a'central aperture It for attaehment to a shaoklepinorthe-endcif-the hoisting line. Within the hub I I-is an'axial cavity'ofpocket 1'1 forming an annular shoulder I 8 on the end face A lower end couplin member such as the hook 211 has an u per shaft or axial hub "2| of reduced diameter adapted to- -extenii freel within the bore ll. At the baseof the shaft 2| is/a lateral extension "22 and upwardly spaced from the ba-seo'n the shaft"'2l 'is" an externalshoiilder 23, this design permitting "the hookfil land the shaft 2| to'be madefrom a single forging to "give maximum stren'gth A series of vertically stacked 'annular'ball"be'aring sets 24a, 24b, and 240., respectivly,"arefitted Within'thebore H in coaxial sideby- 'sidei l'ationship; each bearing s'tfl having aninner and outer race 2'5 and '26 respectivel whose adjacent coope'rati'ng faces are'separated'by spherical balls '2! and are substantially parallel-to the axis of the shaftii. Theadjacent'faces or the inner and outer races 25 and "Z6 have-an'annularg-roove therein in which the-spherical balls '27 seat, so

that they are supported over an arc of their surface and are thus able to transmit both axial and radial loads. In the preferred form I use a bearing having a deep groove with a high degree of osculation to better transmit both radial and axial loads and prevent false Brinnelling under the severe static loads which may be sustained.

The outer race 26 of the lower bearing 25a seats on the annular shoulder 12, and the shaft 2| is inserted from the bottom of the housing It coaxial with the bore I and the annular bearings 24, so that the radial wall of the shoulder 23 bears against the inner race 25 of the hearing 24a and is substantially aligned with the radial wall of the annular shoulder |2. The diameter of the shaft 2| is materially less than that of the bore I to avoid any contact between the shaft 2| and the housing IB and insure that all the loads on the shaft 2| are transmitted through the bearings 24 to the housing It.

A projecting locking means such as the castellated nut 23 threadedly engages the upper end of the shaft 2| and bears downwardly against the inner race 25 of the upper bearing 24c holding the inner races against the shoulder 23. The nut 28 is prevented from turning on the shaft 2| by a cotter key 29 passing through a hole in the shaft 2| and through a pair of radial slots in the castellated surface of the nut. Washers 32 between the bearings 24a, 24b, and 240, space them apart, but a continuous bearing surface surrounds the shaft 2| since each inner bearing race 25 has an axially extended internal sleeve 3| abutting the adjacent sleeves.

The threaded hub M of the upper coupling member If: engages the internal threads |3 of the bore H, and its shoulder |8 bears downwardly against the outer race 25 of the upper bearing 240 to hold the outer races 26 constrained between the annular shoulder 2 and the shoulder N3, the axial cavity fitting freely over the end of the shaft 2| and the nut 28. A radial opening 35 is bored through the annular wall surrounding the threads l3 and into the hub l4, and after the coupling member 15 is in place a suitable threaded plug 36 is screwed therein to prevent separation of the coupling member from the housing 10.

The method of load distribution can now be easily understood. Radial loads on the hook 2e are distributed by the shaft 2| to the inner races 25. They are then carried through the balls 27 to the outer races 26, the lines of force being perpendicular to the adjacent cooperating faces of the races 25 and 26. From the outer races the loads are further transmitted to the walls of the housing surrounding the bore Axial tension loads acting downwardly on the hook 2B are transmitted from the projecting nut 28 on the shaft 2| to the inner races 25. Since the adjacent cooperating faces of both the inner and outer races 25 and 26 are grooved, and the spherical balls 21 are seated within these grooved faces, axial loads on the inner races 25 are distributed to the balls 21 through the grooved walls of the inner race 25. They are then carried across the balls 21 to the opposed grooved walls of the outer race 26, the lines of force being at an oblique angle with the adjacent cooperating faces. From the outer races 26 these axial loads are then further transmitted to the annular shoulder l2 of the housing The hub 14 of the end coupling member 15 is firmly engaged with the housing l and all loads transferred to the housing ID are carried through th h b t '4 the aperture l5 for transfer to a supporting means.

If by dropping or some other operation, axial compression or shock loads are placed on the hook 2D and the shaft 2|, they will be transmitted to the inner races from the projecting shoulder 23. Again they will be distributed to the balls 21 and through them to the outer races 26, the lines of force being at an oblique angle with their adjacent faces. From the outer race they will be further transmitted to the shoulder 18 of the hub M, and directly to the aperture I6.

In the preferred form shown there are three such sets of bearings 24, although of course the number of bearings can be varied and will depend on the size and use of the swivel. The bearings 24 are of standard manufacture and types other than those shown may be used, such as tapered roller thrust bearings. By the use of a series of vertically stacked hearings to distribute the load, I am able to use a smaller race and ball size and consequently reduce the outer diameter of the housing without any reduction in strength. Furthermore, the axial distribution of the bearing surface over the greater length of the shaft 2| prevents any binding within the bearings when a bending force acts on the unsupported end of the hook 20.

The lower end of the housing I!) is counterbored forming the pocket 32 into which a sealing or lubricant retaining ring 33 is fitted. Beneath the ring 33 is the lateral extension 22 of the shaft 2| which protects the sealing ring 33 from damage. By cooperating with the axial hub M, the sealing ring 33 provides a sealed lubrication chamber enclosing the bearings 24 to keep them lubricated over long periods and free from contamination by dirt or moisture.

Fig. 3 shows an optional form of my invention having an end coupling member with an eye 32 in place of the hook 20, and this or other type of end such as clevis, stud, or swedged ends may be used without trouble, as the assembly or disassembly of the swivel is not affected by the size or shape of the end members.

It can thus be seen that I have created a swivel having many operational advantages and an overall streamline shape, without any sacrifice in strength or durability. It is understood of course that modifications may be made in the design and construction by those skilled in the art which will in no way depart from the spirit of my invention, and I do not wish to be limited except as defined in the appended claims.

I claim:

l. A swivel for heavy static loads which includes: an elongated housing having an axial bore therethrough with an internal shoulder adjacent one end; an end coupling member having a shaft extending coaxially into said bore from its shoulder end, said shaft having an upper portion of reduced diameter forming an external shoulder on said shaft adjacent said housing shoulder; a plurality of bearing assemblies each having inner and outer races and spherical balls seated in annular grooves in the adjacent cooperating faces of each of said pair of cooperating inner and outer races, the grooves of said outer races all having axially upwardly presented ball engaging faces and the grooves of said inner races all having axially downwardly presented ball en.-. gaging faces, the lowermost of said outer races resting only on said shoulder within said housing and the balance of said outer races being unyieldi s y upp d in oaxial relationship on said lowermost outer race, the lowermost of said inner races resting only on said shoulder on said shaft and the balance of said inner races being unyieldingly supported in coaxial relationship on said lowermost inner race; a, lock nut threadedly engaged on said shaft and bearing against the uppermost of said inner races to hold said inner races tightly against said shoulder on said shaft; and an opposite end member having a threaded axial hub engaged within the end of said housing opposite said internal shoulder, and bearing against the uppermost of said outer races to hold said outer races tightly against said shoulder within said housing, said hub having an internal cavity of larger diameter than the outer diameter of said inner races for spacing said hub therefrom and receiving said nut and the upper end of said shaft therein.

2. A swivel as described in claim 1 wherein said housing is provided with an outwardly opening recess adjacent said shoulder, a sealing ring mounted in said recess and surrounding said shaft for cooperatively sealing therewith to close the interior of said housing.

CECIL MILLER,

References Cited in the file of this patent UNITED STATES PATENTS Number Number Name Date Sherwood Aug. 24, 1915 Brunner Mar. 13, 1923 Joyner Sept. 20, 1927 Brittain et al June 24, 1930 Burt Apr. 19, 1938 Schwemlein Apr. 30, 1940 King Apr. 11, 1944 Hotchkiss Apr. 25, 1944 Stevens Mar. 4, 1947 Fisher Oct. 28, 1947 Cave Dec. 28, 1948 FOREIGN PATENTS Country Date France -1 of 1922 

